In-bin stapling sorters are well known wherein sets of sheets received in the sorter trays are automatically stapled by a stapler which is normally retracted during sorting operations and is moved to a stapling position to automatically apply one or more staples to the set of sheets in the trays.
In the collating of sheets of paper into sets of documents or in segregating sets of sheets in so called sorting machines, it is desired that the sheets forming the sets or documents be aligned or registered to provide a neat package, particularly when the set or document is to be bound or stapled.
In a variety of moving bin sorters, the trays are arranged in a stack of vertically spaced trays which extend horizontally but at an incline from the sheet entry end of the trays, so that the trailing edge of sheets tend to gravitate into alignment against a flange at the lower end of the trays as the sheets are fed into the trays. At the side of the sheets normal to the trailing edge, the sheets may not be closely registered.
Automatic joggers have evolved which are operated to laterally displace sheets in the sorting trays against a standard or vertical wall forming a part of the frame structure for the sorter or against a side flange on the trays.
Such joggers have involved relatively complicated mechanisms and timing means to cause the jogging action in a sorter which otherwise, has been simplified and made of compact form due to the fact that the trays are sequentially opened to provide a large sheet entry space between trays, while otherwise the trays are close together.
An example of such a jogger is illustrated in U.S. Pat. No. 4,928,941, granted May 29, 1990. In this construction, jogging of the sheets to provide neat, edge registered sets is important in that the sets are stapled while in the trays by a stapler moved to a stapling position as the trays containing the sets of sheets are successively moved to the stapler.
In my U.S. Pat. No. 5,350,164, granted Sep. 27, 1994, co-owned herewith, the jogging of sheets is performed as in the case of U.S. Pat. No. 4,928,941 in that the sheets are moved laterally relative to the direction of infeed into the trays as the trays are moved up and down by the tray shifting mechanism.
In the Coombs and Seay U.S. patent application Ser. No. 100,720, filed Aug. 3, 1993, and co-owned herewith, the sheets are registered at the side edges automatically against a side wall opposed to the jogger member responsive to vertical movement of the trays.
A characteristic which is common to the prior art referred to above is that the sorter trays are not only moved between positions above and below a sheet entry space and spaced apart at the sheet entry space to permit entry of a sheet, but, also, all of the trays are raised and lowered in unison on a lower tray support which supports the outer ends of the trays and is raised and lowered by the cams which raise and lower the trays at the sheet entry ends, as more particularly disclosed in Lawrence U.S. Pat. No. 4,911,424, granted Mar. 27, 1990.
As a result of the movement of the sorter trays vertically in the case of the sorters employing in-bin stapling combined with jogging to a side registration surface at one side of the set of trays, in the stapling sorters referred to above, the sheets are caused to be jogged against a vertically extended, stationary alignment surface, thereby causing drag friction on the side edges of the sheets.
In addition, since the trays are vertically shifted relative to a fixed alignment surface provided on a frame the alignment surface may be provided on a member which extends vertically into a region of the sorter which should be unobstructed for safety or aesthetic reasons.